Method and machine for making clay shingles



D( BROWN April 12, 1938'.

METHOD AND MACHINE FOR MAKING CLAY SHINGLES 5 Sheets-Sheet 1 Filed May 29,- 1935 -April 12, 1938;

D. BROWN METHOD AND MACHINE-FQR MAKING CLY SHINGLES Filed May, 29, 1955 April l2, 1938. D. BROWN METHOD AND MACHINE FOR MAKING CLAY SHIGLES 5 sheets-sheet 5 Filed May 29. 1955 pril 12, 1938. D. BRQWN METHOD AND MACHINE FOR MAKING CLAY SHINGLES Filed May 29, 1935 5 Sheets-Sheet 4 April12,193a. D BROWN f 2,113,717

METHOD AND MACHINE FOR MAKING CLAY SHINGLES Filed May 29, 1935 5 Sheets-.Sheet 5 Patented p 12, 193@ SHINGLES ME'rnoD AND MACHINE rolt l Davis Brown, lLos Angeles, C.

Application May 29, 1935, Serial No. 24,069

9 Claims.

My invention relates to a -clay shingle having new and improved characteristics, and broadly by the term shingle I mean any type of' plastic product which may be hardened, which has the characteristic of a shingle of being' thicker at the buttlthan at the opposite or small end, and thus shingle, the method and the machine over mY prior mtent for a Shingle chine, No. 1,894,394, patented January 17,1933.

In regard to the shingle, an object and feature of my invention is forming a light, corripactlyv pressed and strong shingle having a pronounced thick butt and tapered to the small end, in which the taper is provided by longitudinal ribs extending from a thick transverse bead or butt and towards the small end; the ribs being on the underside. The'web [of the shingle is comparatively thin and substantially of the samegeneral thickness' throughout. shingle is characterized by having a more or less deeply grooved` and ribbed upper surface, the

grooves and ribs being slightly irregular to simulate hand hewn shakes. Also li' desired, the upper surface may have a plurality of designs, such as the roof or grooved surface simulating tl'er` shakes, a criss-cross design .or a smooth surface. All of these may be on the same shingle and they may be varied' in position in accordance with the design it is desired to expose when laying out the shingles.

A further characteristic of the upper surface design of the shingle is that the surface finish may be produced in part by the configuration of extrusion die rolls and in part by the slippage j or extrusion under pressure oi the plastic through the rolls at a higher lineal speed than the peripheral speed of the periphery or pattern surface of the roll. This gives a slight elongation to the design, causing it to diierf in the shingle when so desired, from the design formed when the lineal speed of the shingle and the peripheral surface of the die roll are the same. Y e

Another feature of my invention relates to forming the-extrusion -rolls to'make' the circumference slightly less than the shortest shingle the machine is designed to make, plus a necessary waste piece at .the small end. Thus, there is a slight elongation of the .clay ribbon from the` extrusion press due to the difference of the cross The upper surface of the sectional area of the shingle adjacent the butt an adjacent the small end. Then when longer shingles are desired, the peripheral speedof the rolls is reduced so that the extrusion press causes a distinct slippage ofthe clay through the bite 5 of the rolls and thus develops the desired elongation and slightly alters the upper surface pattern. The operation of the cutting. knives is so regulated and timed with the rolls as to form a main or primary cutat the butt end anda secm ondary cut adjacent the small end, thereby developing a slight wastage piece between the small end of one shingle and the butt end of the next proceeding shingle. By forming a thick trans'- verse bead or rib I may develop a shingle having 15 the appearance of an unusuallythick end which is highly desirable as being ornamentalA when the shingles are laid.

Another feature oi my invention as to the meth-y od and machine involves supporting the leading end of the clay ribbon on a moving conveyor, 20 operating at a surface speed slightly higher than the peripheral speed at the bite oi the rolls, whereby a .slight tension or pull is .developed on and the rolls from bringing compressive stresses on the thin die pressed ribbon which might cause a buckling. However, in .order to avoid too great a tension, the upper surface of the conveyor `is lubricated.

Another object and feature of my invention relates to the method off cutting the extruded clay to form thes'eparate shingles. This involves forming a rst cut at the butt end of the shingle immediately as it leaves the' extrusion die rollers, this cut being made through preferably a thickened flange or butt end bead. This cut is made while the leading end `of the succeeding shingle 4is being fed towards the endless belt conveyor and hence the severed shingle may be iedawayV from the succeeding shingle beingextruded` and thereby avoid any end pressure on such succeed-a ing shingle. I

A further object and feature-oi' my invention involves maintaining the cutting knives both for making the butt and the small end cut always transverse to the extruded shingle, that is being at right angles to the upper surfae of 'the shingle. I .This feature involves bringing the cutting knives into contact with the shingle while being extruded from the press and the die rollers and having the leading or small end supported on the relatively high speed conveyor belt. These knives are given a combined motion transverse to the shingle to make square cuts at both ends of the shingle and the ribbon, thus preventing the extrusion pressN 25? at the same time the knives travel longitudinally at the same speed as the progressive movementl of the shingle so that the cut is gradually made while the clay forming the shingle is traveling after being extruded and die pressed to the desired shape on the upper and lower surfaces.

Another feature of my invention Arelates to associating with the cutting knives, a plurality of punches, these being spaced from the knife cutting the small end. These punches operate in the same manner as the knives to form perforations in the small end of the shingle to provide nail holes. The punches are manipulated to have the combination transverse and longitudinal move' ment in order that the clay of the shingle be not distorted where the holes are punched.

My invention is illustrated in' connection with the accompanying drawings, in which, I

Fig. 1 is a side elevation of my invention taken on the section line I I of Fig'. 2 in the direction of the arrows or in the direction of the arrow I of Fig. 3.

Fig. 1a is an enlarged elevation of the cam guide and associated parts of Fig. 1.

Fig. 2 is va, vertical section on the line 2 2 of Fig. 1 in the direction of the arrows, the extrusion screw being omittedl from the extrusion press and the remote parts of the machine being omitted.

Fig. 3 is an opposite end elevation taken in the .direction of the arrow 3 of Fig.v 1, the remote end portions of the machine being omitted.

Fig. 4 is a partial longitudinal section on the line 4 4 of Fig. 2 in the direction of the arrows,

showing a portion of the extrusion press in section and the cutting mechanism in elevation, the cutting mechanism"` being shown in an elevated position. f

Fig. 5 is partial section similar to Fig. 4, but illustrating the cutting mechanism in cutting position.

Fig. 6 is a partial transversesection on the line 6 6 of Fig. 1 in the direction of the arrows, on a larger scale than Fig. 6, to illustrate mainly the extrusion die rollers.

Fig. 7 is a side elevation taken in the direction of the arrow i of the adjusting timing gear, the

fied construction of extrusion rolls having coniiningplates at each edge instead of flanges formed integral with the rolls.

Fig. 12 is a perspective view of the shingle illustrating the upper surface.

Fig. 1 3 is a perspective view ofthe shingle of Fig. 12, showing the undersurface.

Fig. 14-is a transverse section of the shingle on the line |4--l4 'of Fig. 13` in the direction of the arrows."

Fig. 15 is a transverse section of Fig. 12 on the line i-l of Fig. 13.

Fig. 16 is la perspectiveview of the upper surface of 'a modiied shingle construction having the same design from the butt to the small end.

AThe extrusion press designated generally by' the numeral Il may be of -the conventional type which is illustrated as having an outer cylindrical casing or housing l2 with a hopper structure I3 for the feed of the clay. -This cylinder has a ange I4 at one end to which is attached the converging flanged head I5; this tapering or converging to' a rectangular mouth I6. Such mouth has horizontal upper' and lower edges i1' and lateral edges I 8. (Note Figs. 2 and4). Secured to the mouth is the extrusion die I9 which has short vertical side edges 20 and upper and lower edges 2l. These upper and lower edges converge towards the center so that the measurement at the center as indicated bythe measurement line 22 is slightly less' than the marginal vedge measurement 20. This gives a. die voriiice which is much longer on its horizontal measurement than on its vertical measurement. Secured to the side edges of the extrusion die and preferably formed integral therewith, there are triangular shaped end projections 23 to conne the clay at the margins of the extrusion die.- 'Ihe clay is pressed outwardly through the die by any extrusion screw 24 mounted on a shaft 25. The screw and the shaft may be of the conventionaltype and the shaft driven by any suitable mechanism at the end 26 remote from the extrusion die.

'I'he main kportion of my machine utilizes a frame 30 which may be of any suitable type and has upper and lower extrusion die rollers 3| and 32 mounted therein. These die rollers are mounted on shafts 33 and 34 respectively and suitably journaled in the frame 3l).v Each of these die rollers has a marginal ange 35, the triangular projections 23 being aligned with these iianges, the flanges preferably contacting and the' projections thus preventing clay being forced outwardlyat the margins of the die rolls.

The configuration of the surface of these rolls is such as to form the particular design on the upper and on the undersurface of the shingle.

'Ihe upper 'die is illustrated as having somewhat irregular longitudinal grooves 36 and between these grooves there are irregular ridges, the

general direction of'the ridges and the grooves being circumferential of the die. Another section of the upper die has criss-cross intersecting ridges and grooves 31, the remainder of the die having a smooth surface 38. In this upper die the outermost measurement of the longitudinal ridges of the portion 3S, the criss-cross ridges of ysmooth section will be in a horizontal plane.

The lower die roller 32 has a transverse depression 40 (note Figs. 6 and 9) and from this extends circumferential grooves 4I spaced apart by circumferential ribs 42. 'I'he circumferential grooves gradually decrease from their commence'- ment adjacent the transverse depression 40 and merge at 43 to the smooth cylindrical surface 44. The cylindrical section is at the same radius indicated at 45 as the outer periphery of the ribs 42. Thus as these dies are driven in rotation at a constant speed, the direction of rotation is indicatedby the arrows 46 and 41 of Fig. 9.

Thetype of shingle` illustrated is designated generally by the numeral 50 and is illustrated in detail in Figs. 12, 13, 14, and 15. In this construction the upper orexposed face 5l of the shingle is formed 'by the section 35 of the upper amarre i I made in the manner hereinunder described, giving a cut edge 55 thus'forming two semi-beads '55 and lil. The semi-bead 56 is at the base or lower end of the grooves 58 (noteFlg. 13) formed by the ribs di. The grooves 8| of the lower .roller 32 form the longitudinal ribs 5d. The die rollers are so shaped that the ribs decrease inheight ory thickness while the ribs l on the lower die roll are of such shape that the thickness of the shingle on the measurement t@ is substantially constant from adjacent' the bead 5d to the thin end 5| ofthe shingle (note Figs. 1i and 5).

Due to the fact that thereis a greater quantity of clay passing between the die rolls adjacent the butt end than at the small end @l of each shingle, and the die'rolls operate at the same or constant surface speed, there is a slight slippage between the extruded clay and the die rolls, causing an .elongated deformation oi the' design 5t on the upper surface of the shingle indicated by the numeral @it (note Fig. `12). Also the criss-cross ribs are deformed slightly at 'the portion tit adjacent the smooth surfaced section 5t. In the operation of the machine, a secondary cut is given at the position tl (note Fig. 5) spaced from the first cut 55 through the bead 5d. This forms a waste section d5 (note Fig. l). The waste sec-s tion may be changed in length in order to change the overall length of the shingle. The shingle thus has a verticalbase end forming the exposed lower edge indicated at t5 in Figs. 12 and 13, two parallel side edges di and the small upper edge th; the edges 5d and @t being parallel. During the severing of the shingle to make the cut at the base and to trim ed the waste end, perfora tions t@ are also formed in the shingle adjacent the small end dd. These form nail holes for securing the shingle to a roof or similar structure.

in order to form this type oi shingle I employe. rst endless belt conveyor l5 which operates over pulleys it on the pulley shaft 'il and a complementary pulley 'le on the pulley shaft it. (Note Figs. l and 4.) The upper run 8d of this conveyor is driven 'at a higher surface speed in the direction of the arrow Bithan the peripheral die face of/,the pulleys. Thus there is a slight pull on the portion of the clay forming the shingle after its extrusion through the die rollers. This pull or tension is sufiicient so that the die rollers do not have to force-the shingle along the upper run of the endless belt and such slight pull tends to facilitate the slight slippage of the clay when extruded between the die rolls in order to form the slight deformation on the upper side of the shingle. Moreover, this slight increase in speed causes a slight separation or gap indicated at t2 vbetween two contiguous shingles, this gap being formed at the cut 55 through the full bead dd (note Figs. 4 and 5).

The shingles'after being cut during their travel on the endless conveyor 75 to the desired'length by the mechanism hereinunder detailed, are transferred to a second endless belt conveyor 85. This operates over a rst set of pulleys 86 on a pulley shaft 81 (note Fig. l) and an end pulley 88 having a pulley shaft 89. This belt'is driven with its upper run 90 operating at a hlgher surface speed in the direction of the arrow 9| than The lower die forms the upper run er or the ,endless bea 15. v'rms telt d5 is usually much longer than the belt 'l5 in order to develop aconsiderable spacing of the succeeddie roll 32 and the pulley i6 (note Figs. 4 and 5) and extends transversely at least-the full length of the die rolls to support the extruded shingle on its transfer from the die rolls to the upper run 8|! of the belt li-i. This also forms an abutment for the initial cut which forms the out 55 through the whole bead 5d. The mechanism for making this cutis hereinunder detailed. There is also a second bridging plate d5 between thedischarge end of the upper run t@ of the endless belt 'l5 and the uppervrun @t of the second endless belt 85; this plate being located between the pulleys 'i8 over which the belt l5 operates and the pulley t@ over which the beltt operates. ing lplate is supported in the frame ofthe machine and extends at least the iull width of the conveyor belts. This bridging plate t5 supports the .shingle in its transfer from the upper run iid of the first belt 'l5 to the upper run 9U of the second belt dii.

When it is desired to split the shingles longitudinally to make these narrower than the standard width, l2 employ a splitting mechanism imi' which employs a rotary splitting knife itl made in the form of a disk suitably weighted mounted on a cutter knife shaft HD2; the shaft being journaled in arms itt hinged or pivoted at ltd to the frame of the machine. This splitting knife or disk is located to operate above the bridging plate @t and it will be obvious that if desired one or more of these rotary splitting knives may be utilized if it is desired to split the shingle longitudinally in two parts or more. However, as above mentioned the `use of this splitting knife is optional and is not used where the full width shingle is desired. The splitting knives also split the waste segments t5.

The cutting mechanism for giving the transverse cuts is designated generally by the assembly numeral il@ (note Figs. l, 3, 4 and 5). This mechanism employs a blade holding frame Hl. This may be formed of angle-shaped members i l2 having pivot pins i iti extending therethrough. These pins each have a lower swivel head iid mounted thereon between the angles. the swivel headhaving a hub M5 through which the pivot pins extend and a boss H5 (note Figs. 1 and 3). To each boss is secured a link li'l (note Figs. l and3): these being preferably threaded in the boss H5 and secured by lock nuts ii.

The upper ends of the links H1 are mounted in an upper swivel head 20, eachlof which has 'a transverse or horizontal hub l2i fitting on a crank pin i252 which crank pin is 'secured to a counter-balanced crank arm |23. Each crank arm is attached to a crank shaft |24 and hasa counter-weight mi (note Figs. 1 and 3). The crank pins have a head |26 and are secured by nuts i271. Extending downwardly from each hub lill there is an arm izrhaving a sleeve |29 secured integral therewith, in fact, the hub arms.

This brldgon each link, thus giving a resilient and downwar pressure to the blade carryingA frame The blade carrying frarnehas a first xed knife |35, this preferably being in the form of an angle and having a horizontal cutting edge |36. This blade is positioned adjacent the die rollers and forms the base cut in a manner hereinunderdetailed. A'secondary adjustable blade |31 has a cutting edge similar to the first blade and is adjustable on the blade carrying frame so that the distance between .the blades and 31 may be adjusted to form the cut 64 which severs -the small end 6B oi' the shingle at variable distances from the base cut 55 in order to vary the length of the shingles. This blade also varies the length of the waste piece 65. In order to form the nail holes 69 a pair of punches |38 are secured to the blade carrying frame I I I preferably to the angles ||2. adjusted at variable distances from the blade |35 and also from the blade |31 so that 'the nail holes 69 may be the desired distance from the small end 68 of the finished shingle. The material perforated from the clay by these punches is pressed upwardly through the tubular punches'and discharged on the top of the shingles as they pass through the cutting mechanism.

-The mechanism for guiding the cutting assembly employs a cam guide designated by the assembly numeral |40 (note Figs. 1 and 1a). This cam guide employs a rigidly mounted vertical frame at one side of the machine and has a down- Wardly sloping cam path |4| defined by the guide structures |42 and |43, and a vertical guide path |44 defined by the vertical surfaces |45 and |46. 'I'here is a longitudinal cam path |41, this being open at the bottom |48 andl dened at the'top by the tilting restraining plate |49. 'I'his is pivoted at |50 and has a normal horizontalilange |5I, an arcuate end |52, a stop shoulder |53, adapted to contact the stop |54 attached to the structure |43. A cam channel |55 for upward movement is defined by the'concentrlc guide surfaces |56 and |51, the surface |56'having a vertical guide Wall |58 and the surface |51 having an inwardly turned end |59. 'I'he guide walls |43 and |51 join at the top in a curved connection end |60. A guide latch |6| pivoted at`|62 has a l normal horizontal flange |63 and a vertical flange The cam guide' channel having the various components above described is for guiding a guide pin |65 which is rigidly secured to the blade holding .frame being attached to the vertical A iiange of the angles ||2.

The end of this pin extends into the cam channels above detailed. If

it were not for this guide channel and the guide in dotted lines at |61 (Fig. 1a) the center of rotation being indicated by the center point |68. The equivalent circle |61 is indicated dotted on Fig. l. It is desired that when the links reach the point |69 that the cuts be made by the blades |35 and |31 that these bladesl have a vertical movement during their travel to the point |10 on their circle of rotation. 'Ihis causes them to cut to a depth measured by the cord line |1| betweenn These punches are tubular and may be The two cranks |23 rotate at the sameV the points |69 and |10 and the lowermost point |12 occupied by the pin |65. Thisdevelops a. vertical movement indicated by the measurement |13 which is sumcient to cut through the clay of the shingles and form the cut 55 at the full bead 54 and also to make the secondary end cut 64.

The speed of. rotation of the cranksl |23 and hence of the cuttingv assembly during its lcutting stroke is synchronized so that the guide pin |65 travels between the points |69 and |10 on the circle |61 at the same rate as the clay shingle advances from theextrusion press and on the upper run' 80 of the first conveyor 15. Thus as the guide pin moves at this rate the cutting blades manifestly must move at the same speed relative to the extruded clay forming the shingles.

The pin |65 is g'uided vertically prior to the blades entering the clay by the vertical channel |44. After the blades are withdrawn at the point of travel indicaiedat |10, the pin follows the, path indicated by the dotted lines |14 and engages the horizontal iiange |5| of the restraining plate |49. This plate if desired is guided by a pin |15 operating in an arcuate slot |16 in the xed frame structure. If the pin |65 rises too high and engages the inwardly curved surface |59, it is guided into the channelA |55. At the top of the stroke oi this channel |55 it contacts the guiderlatch |6| and is lifted and the pin is guided into the downwardly sloping channel |4I, this latch preventing the pin from again entering the channel |55 and being lowered in a reverse direction. During the downward travel in the 'channel |4I, 'as this is vdisplaced from the circle vof rotation |61, the links I1 are inclined from their pivotsto the cranks |23. towards the dischargeend of the machine, but during this part of the travel the cutting blade supporting frame is elevated high above thebelt and the shingles being extruded. It will thus be seen thaty when the machine as to the extrusion and to the movement of the cutting frame are properly synchronized, that the ilrst cutting blade |35 always cuts through the butt end of the shingle to be formed, forming the main severing cut 55 at the exact center of theA enlarged or whole bead 54 (note Figs. 4 and 5).

In order to lubricate the upper surface of the iirst conveyor, I.provide a friction driven lubricating roll |30 (note Figure 1) which dips into a lubricating tank IBI and'depositsthe lubricant on the lower run of the first conveyor belt 15. This lubrication of the belt thereby facilitates the slippage of the strip forming the 'shingle as it is passed through the extrusion press. The extrusion rolls are also lubricated by lubricant jets |82 and |83 (note Figs. 6 and 9). l

'I'he drive mechanism I have developed for the rolls and the conveyors, employs a belt pulley |05 'indicated 'as driven by the belt |66., lThis drives the shaft |81 oi.' a variable speed belt drive |90 which may be of a standard character.- thus driving the shaft |89. This has a pinion` |90 meshing with a largegear |9| (note Fig. 2) secured to the shaft |92 of the upper extrusion roll 3|. The lower roll is driven by a gear drive |93 on the shaft |92 to the gear |94 on the shaft |95 of the lower extrusion roll 32.

The timing of the cutters in reference to the rolls is by the driveconnection designated by the assembly numeral |96. On the' shaft |92 there is a iixed or keyed sleeve |91 (Figs. I and 8)' having a. iange |90 and secured to the flange there is a sprocket wheel |99 having slots 200 through which'extend the clamping bolts 20|, thus al lowing a considerable displacement oi the amavis sprocket wheel it in reference to the sleeve `Ili'l and hence the shaft |92. A sprocket chain 202 operates two sprockets 2cd and 2W, operating the crank shafts IM. The sprocket chain also passes over an idler sprocket 2te.

Thus it may be seen that the timing of the actuation of the cranksl for thev cutter may be properly synchronized with the extrusion ci' the clay for it is essential that the main or primary cut Eli be made exactly through the center of the full bead or rib Eid. The circumference of the die surface of the extrusion rolls is slightly less than the 'lineal length of the shortest shingle between the successive full beads 5t. There is a slight elongation of the small end portion of the shingle in reference to the butt end, due to the 'butt end having much thicker ribs and hence a larger cross sectional area, even when the peripheral speed of the extrusion rolls is the same as the lineal speed or the ribbon oi clay.'

With my present construction it is desired to maintain the speed ci the extrusion screw constant and thus maintaining a substantially constant pressure on the extruded ribbon of clay through the die it and the bite of the extrusion roll. 1

To iorm longer shingles the speed of the whole mechanism may be retarded by the variable speed drive ltd. This cames the extrusion die rolls 'to have a slower peripheral speed in reference to the lineal extrusion speed ci' the ribbon oi clay. Therefore there is a slight elongation of the patterns of the upper surface of the shingle.l

driving connection between the clay working ma-4 chine with. the extrusion press and the shingle iorrnlng machine, to illustrate suitable mechanism for changing the lineal speed oi extrusion ci the plastic ribbon from the extrusion press il.

In this illustration the extrusion press ils shown V as being supplied with clay by a pugmill 2id hav-luga rotating shaft ill with cutting blades 2li. therein. The pugmill is supplied with material by an endless conveyor belt 2id. This latter is loaded by means of a hopper 2id having an adjustable gate 2lb. l

The drive mechanism is illustrated as having a line shaft 2id, a rst belt drive itt to the pullerl l lid which forms the main drive connection to the extrusion rolls andall of the mechanism.v for pressing, cutting and feeding the shingles. The auger 25 of the extrusion press has ageared con- 2id. The feeding belt 2li has anl operating above mentioned. y

tive lineal speedA through the extrusion rolls, the speed of the auger could be varied somewhatin the manner set forth in my patent application Another manner to increase the lineal speed oi the material extruded through the oricelt is by varying the opening of the gate uit oi the hopper 2id. Thusi provide a considerable nexibility in the operation of my present entire mechanism, by either varying the speed of 'the errtrusion rolls, the speed of the auger or the quantity of material fed tothe auger. I may7 supply 'and work the clay prior to its reaching the extrusion press in accordance with my prior Patent No. 1,907,731, Clay tempering machine, patented `-May 9, 1933, or in accordance with thepatent to J. C. Schaden No. l,dl9,9a6, patented June 20, 1922, for Feeder. There are .also a number o shaft il@ with a belt drive 22d from the same line v shaft. They shaft @il of the pugmill has a geared connection 22H to the belt drive 222 connecting to the same line shaft. With this mechanism it is possible to maintain a constant drive to the feeding belt 2li and thus to the pugmill 2id whichv supplies material to the auger 25 ci' the extrusion press ll. A. constant speed drive may thus be given tb the pulley itt of the shingle forming mechanism and this machine has'the variable speed drive idd. Therefore the drive to the exi trusion rolls may be retarded while the feed of the ribbon-through the extrusion `orifice it is maintained at a substantially constant lineal speed. However, should it be desired to change the relatypes of feeding machines on the'marlret which may be used with my shingle forming machine. In. Fig. ll I illustrate a. vertical transverse section through a modified construction of extrusion rolls. In this li have an upper roll dit and a lower roll 22d; these may have the desired con.- figuration on their surfaces. At each side of these rolls there is a xed lplate 2id', such plates connecting with the mouth or lined extrusion die of the extrusion press to confine the ribbon of plastic material at the marginal edges of the rolls. These plates therefore are a substitute for the anges 3b on the rolls as shown. in Fig. d.

lin Fig. 16 I illustrate a modiiiecl type ci upper face for the shingles, the shingle as a whole being designated by the numeral 225i having the butt end 22d and the small end 22T?. In this case the design 22d on the upper surface .is preferably formed of grooves and ridges similar to the design indicated at .5l in Fig'. 12. When these eri- `tend from one end to the other face of the shingle they give the appearance oi hand mad-e shakes.

in the construction of the surface ot `Fig. lo, whenA the ribbon of clay is extruded at a higher lineal speed than the Aperipheral speed ci the y extrusion rollers, there is a slippage which causes a'slight drawing out of the design on the upper surface, so this does not have absolutely true markings corresponding with accuracy to the .design on the upper extrusion roll.

It will be noted that a characteristic `feature of the shingle formed by my machine and the meth-` od of operation is thaty it is quite light, the main sol body of the web portion betweenvthe ribs being of substantially constant thickness, except for variations caused by the upper Iface design. The ribs 'taper in thickness from the butt towards the small end, the butt having the thickened bead but the vribs are preferably of the same width from one end to the other. Therefore in causing an elongation in extrusion to develop longer shingles, the slippage of the clay through the grooves of the lower extrusion roller forms'clear cut ribs. N v As above described, in the type of shingle of Fig. l2, the design at the butt and the small end may be changed by varying the position of the upper roll in reference to 'the lower roll so as. to produce shingles having a different exposed surface when laid on a roof. l Various changes may be made in the details of construction Without departing from the spirit or scope of the invention as defined by the appended claims.

I claim.: 1. In a' clay working machine, lmeans to form a moving strip of lplastic material combined with a cutter mechanismhaving a biade holding frame, a pair of blades mounted on said frame, a pair of parallel links pivotally connected to the frame, a crank connected to each link,` means to rotate the cranks in a circular motion, a fixed cam, a.

guide pin on the blade holding frame, the said guide pin and the cam guiding the blades in making an incision and in being withdrawn from the strip to be always at right angles tov the axis of the strip, the said links and cranks permitting the blade holding frame to move at the same lineal speed as the strip While making the incisions and I supporting the extruded strip beyond the point oi extrusion and exerting a slight tension while supporting the strip to. prevent the strip buckling under the pressure of extrusion, during the movement of the strip making a rst incision adjacentthe point of extrusion to sever the strip into a plurality of fixed lengths and -at the same time making a secondary incision spaced from the rst incision to divide each xed length into two portions, one portion forming the article to be, made and the other portion being fa waste.

-4. In a clay working machine, means to form a moving strip of plastic material combined with a cutter mechanism having a blade holding frame, a. pair of blades mounted in said frame, a pair of'parailel links pivotally connected to the frame adjacent' opposite ends thereof, means to develop a combined up and down and horizontal' movement of the links, a xed cam, a guide pin on the blade holding the. frame, the said guide pin and the cam guiding the'blades in making an incision and in being withdrawn from the strip e to be always at right angles to the axis of the strip, the means for developing the motion of the links being operative whereby when the blade holding frame moves-in. thesame direction as the strip, the strip and the frame have the same lineal speedY while the blades are making the incision and being withdrawn from the stri I 5. In a clay working machiney as clalmed in claim 4, the cam having a cam path with thepiri tting therein when the blades are out of engagement with the strip, a tilting restraining plate having a horizontal guide element, the pin passing below said element when the blades engage the strip, the said element being adapted to be moved upwardly by the pin and the restraining plate being operative -to prevent a reverse motion of the. pin in the cam path.

6. In a clay working machine as claimed in claim 4, the cam having a cam path with the Vpin tting therein when the blades are. out of contact with the` strip, said path having an upward curved lead and a downward substantially straight sloping lead, there being a movable guide latch at thefpoint of junction at the top of the curved and the inclined straight leads, said guide latch being moved by the saidpin and the guide latch being adapted to divert the pin downwardly into the sloping straight channel.

. spaced from the ends ci the4 shingle.

7. A clay working machine having means for extruding a ribbon of clay, a ilrst conveyor re ceivlng the ribbon and movable at the same lon gitudinal speed as the ribbon, a cutter mechanism having a irst and a second blade, said mechanism having a pivotal mounting forvthe blades, such pivotal mounting beingtransverse to the direction of movement 'of the ribbon, means to operate saidV mechanism to develop a parallel motion. of the blades to make incisions in the ribbon, the blades while the incision is being made, being movable at the same speed as the ribbon of clay and forming the incisions at right angles to the direction of movement of the ribbon, the cutter mechanism having means to withdraw the blades at the end of the incision while the blades are travelling at the same speed as the ribbon and means to return the blades above the ribbon to their initial position for a second setfof incisions, an outieeding conveyor movable at a higher speed than the speed of the ribbon and of the first conveyor, the blades being adapted to cut the ribbon into' shingle lengths and to also cut a small waste piece of ribbon, the second conveyor being l.adapted to'separate the successive shingle lengths and the waste pieces.

8. A clay working machine as claimed in claim '1, the extruding means including al pair of complementary rollers through which the ribbon extends having a configuration for forming aetransverse Jib land longitudinal grooves extending from the rib and a section adjacent the rib without longitudinal grooves, the blades including a rst blade positioned to make an entering `incision adjacent the rolls and a, second blade adjustable longitudinally as to spacing from the rst blade, means to time the incisions of the blades with the rolls whereby the ilrst blade al- -ways makes an incision through the rib of the' leading ribwhereby the shingle 1ength 1s always provided with grooves terminating in positions 9. A' clay working machine having an extrusion means for a ribbon of clay including apair oi' complementary rollers with their axis transverse to the direction of movement of the ribbon said. rollers having a conguration to form a series of transverse ribs, a series of longitudinal grooves, the grooves terminating spaced from a transverse rib, a cutter mechanism having pivotally mounted cutters, the pivots being transblades to make the initial movement of an incision while -closest to the rolls, the blades being` movable away lfrom the rolls at the same speed as the movement oi' the ribbon, the cutter mechanism and the rolls having a timing interconnection whereby the first blade always makes an incision throughf the rib to form one end of the shingle a d the second blade always makes an incision thr ugh'the portion of the ribbon adjacent another rib and spaced from the termination of" Athe grooves, therebyv :forming a shingle length with the grooves closed at both ends, thetwo incision's also forming, a waste section oi.' the rib- DAVIS BROWN.' 

